Fair Value Disclosures (Details 1) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2004 Senior notes due 2011 at 6 3/8%	Nov. 30, 2012 Senior notes due February 1, 2014 at 5 3/4%	Nov. 30, 2011 Senior notes due February 1, 2014 at 5 3/4%	Jan. 28, 2004 Senior notes due February 1, 2014 at 5 3/4%	Nov. 30, 2012 Senior notes due January 15, 2015 at 5 7/8%	Nov. 30, 2011 Senior notes due January 15, 2015 at 5 7/8%	Dec. 15, 2004 Senior notes due January 15, 2015 at 5 7/8%	Nov. 30, 2012 Senior notes due June 15, 2015 at 6 1/4%	Nov. 30, 2011 Senior notes due June 15, 2015 at 6 1/4%	Jun. 02, 2005 Senior notes due June 15, 2015 at 6 1/4%	Nov. 30, 2012 Senior notes due September 15, 2017 at 9.10%	Nov. 30, 2011 Senior notes due September 15, 2017 at 9.10%	Jul. 30, 2009 Senior notes due September 15, 2017 at 9.10%	Nov. 30, 2012 Senior notes due June 15, 2018 at 7 1/4%	Nov. 30, 2011 Senior notes due June 15, 2018 at 7 1/4%	Apr. 03, 2006 Senior notes due June 15, 2018 at 7 1/4%	Nov. 30, 2012 Senior notes due March 15, 2020 at 8.00%	Feb. 07, 2012 Senior notes due March 15, 2020 at 8.00%	Nov. 30, 2012 Senior notes due September 15, 2022 at 7.50%	Jul. 31, 2012 Senior notes due September 15, 2022 at 7.50%	Nov. 30, 2012 Carrying Value Level 2 Senior notes due February 1, 2014 at 5 3/4%	Nov. 30, 2011 Carrying Value Level 2 Senior notes due February 1, 2014 at 5 3/4%	Nov. 30, 2012 Carrying Value Level 2 Senior notes due January 15, 2015 at 5 7/8%	Nov. 30, 2011 Carrying Value Level 2 Senior notes due January 15, 2015 at 5 7/8%	Nov. 30, 2012 Carrying Value Level 2 Senior notes due June 15, 2015 at 6 1/4%	Nov. 30, 2011 Carrying Value Level 2 Senior notes due June 15, 2015 at 6 1/4%	Nov. 30, 2012 Carrying Value Level 2 Senior notes due September 15, 2017 at 9.10%	Nov. 30, 2011 Carrying Value Level 2 Senior notes due September 15, 2017 at 9.10%	Nov. 30, 2012 Carrying Value Level 2 Senior notes due June 15, 2018 at 7 1/4%	Nov. 30, 2011 Carrying Value Level 2 Senior notes due June 15, 2018 at 7 1/4%	Nov. 30, 2012 Carrying Value Level 2 Senior notes due March 15, 2020 at 8.00%	Nov. 30, 2011 Carrying Value Level 2 Senior notes due March 15, 2020 at 8.00%	Nov. 30, 2012 Carrying Value Level 2 Senior notes due September 15, 2022 at 7.50%	Nov. 30, 2011 Carrying Value Level 2 Senior notes due September 15, 2022 at 7.50%	Nov. 30, 2012 Estimated Fair Value Level 2 Senior notes due February 1, 2014 at 5 3/4%	Nov. 30, 2011 Estimated Fair Value Level 2 Senior notes due February 1, 2014 at 5 3/4%	Nov. 30, 2012 Estimated Fair Value Level 2 Senior notes due January 15, 2015 at 5 7/8%	Nov. 30, 2011 Estimated Fair Value Level 2 Senior notes due January 15, 2015 at 5 7/8%	Nov. 30, 2012 Estimated Fair Value Level 2 Senior notes due June 15, 2015 at 6 1/4%	Nov. 30, 2011 Estimated Fair Value Level 2 Senior notes due June 15, 2015 at 6 1/4%	Nov. 30, 2012 Estimated Fair Value Level 2 Senior notes due September 15, 2017 at 9.10%	Nov. 30, 2011 Estimated Fair Value Level 2 Senior notes due September 15, 2017 at 9.10%	Nov. 30, 2012 Estimated Fair Value Level 2 Senior notes due June 15, 2018 at 7 1/4%	Nov. 30, 2011 Estimated Fair Value Level 2 Senior notes due June 15, 2018 at 7 1/4%	Nov. 30, 2012 Estimated Fair Value Level 2 Senior notes due March 15, 2020 at 8.00%	Nov. 30, 2011 Estimated Fair Value Level 2 Senior notes due March 15, 2020 at 8.00%	Nov. 30, 2012 Estimated Fair Value Level 2 Senior notes due September 15, 2022 at 7.50%	Nov. 30, 2011 Estimated Fair Value Level 2 Senior notes due September 15, 2022 at 7.50%
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Senior notes, rate	6.375%	5.75%	5.75%	5.75%	5.88%	5.88%	5.875%	6.25%	6.25%	6.25%	9.10%	9.10%	9.10%	7.25%	7.25%	7.25%	8.00%	8.00%	7.50%	7.50%
Senior notes payable																					$ 75,911	$ 249,647	$ 101,999	$ 299,273	$ 236,826	$ 449,795	$ 261,430	$ 260,865	$ 299,129	$ 299,007	$ 345,209	$ 0	$ 350,000	$ 0	$ 77,679	$ 232,500	$ 106,003	$ 270,000	$ 248,751	$ 401,625	$ 305,413	$ 235,519	$ 325,500	$ 251,625	$ 390,250	$ 0	$ 378,000	$ 0